Exactly. If metabolizing our primary fuel storage was so stressful, we would have died out long ago.

You can't just dismiss 2.5 million years of evolution.

While I and even Mark agree that Paleo re-enactment is silly, this statement is simply wrong biologically. There have been a few human adaptations such as lactose tolerance after weaning but, genetically, we are exactly the same as our Hunter Gatherer ancestors.

I don't see why fat usage being stressful and fat usage being evolutionarily advantageous are mutually exclusive.

I don't see why fat usage being stressful and fat usage being evolutionarily advantageous are mutually exclusive.

Mother Nature doesn't select the most stressful method as the primary one.

This said it well: (originally posted by dwkdnvr)

"The fact that we can store only a very minimal amount of carbs but a great amount of fat seems to point clearly to an expectation that we'd run off fat as the base of our metabolism - the only other rational conclusion is that carbs were ubiquitously available and meal timing/frequency were entirely predictable; this seems absurd on it's face. If metabolizing stored fat were 'stressful' to the point of compromising health, one has to think that an adaptation towards higher glycogen storage would have become dominant. Or, equivalently, an alternate fat metabolic pathway that is less stressful would have been selected."

Mother Nature doesn't select the most stressful method as the primary one.

This said it well: (originally posted by dwkdnvr)

"The fact that we can store only a very minimal amount of carbs but a great amount of fat seems to point clearly to an expectation that we'd run off fat as the base of our metabolism - the only other rational conclusion is that carbs were ubiquitously available and meal timing/frequency were entirely predictable; this seems absurd on it's face. If metabolizing stored fat were 'stressful' to the point of compromising health, one has to think that an adaptation towards higher glycogen storage would have become dominant. Or, equivalently, an alternate fat metabolic pathway that is less stressful would have been selected."

+1

While Peat makes a lot of good points and is extremely interesting to me, the data I've seen suggests that fat is far less stressful to metabolize than sugar. That's not to say burning glycogen is toxic (as some people make it out to be to support some agenda), but fat clearly is the less stressful fuel. That's why we burn it at rest when our body is relaxing. There's just no way on a cellular level that we are more stressed while resting than while at full sprint or deadlifting 300 pounds. That is not a logical assessment.

I also can't see how eating fish is unhealthy and stressful, either. Coastal areas with high fish consumption are some of the healthiest cultures on the planet. Look no further than the Japanese or the Samoans. PUFA from fish and nuts =/= PUFA from refined vegetable oils and grains.

Last edited by ChocoTaco369; 07-12-2012 at 05:55 PM.

Don't put your trust in anyone on this forum, including me. You are the key to your own success.

I don't know if this is the best place to post this, but Mark's recent post of blogs got me to this guy. Seems a good spot given the current discussion. He's got some great stuff for us science minded folks.....I'd start with this one Lucas Tafur: Bioenergetics. He seems to present good data without an agenda (well I'm sure he does have his biases)....but fairly balanced, especially when you consider the crux of this post is mathematically based.

While Peat makes a lot of good points and is extremely interesting to me, the data I've seen suggests that fat is far less stressful to metabolize than sugar. That's not to say burning glycogen is toxic (as some people make it out to be to support some agenda), but fat clearly is the less stressful fuel. That's why we burn it at rest when our body is relaxing. There's just no way on a cellular level that we are more stressed while resting than while at full sprint or deadlifting 300 pounds. That is not a logical assessment.

I also can't see how eating fish is unhealthy and stressful, either. Coastal areas with high fish consumption are some of the healthiest cultures on the planet. Look no further than the Japanese or the Samoans. PUFA from fish and nuts =/= PUFA from refined vegetable oils and grains.

Yeah, I can feel all that stress from my seared ahi dinner. People have lived by coastlines as long as there have been people.

We burn glycogen for a fast burst of energy, to catch dinner or avoid becoming some critter's dinner. Living your whole day in that fight or flight fast burn just strikes me as the ultimate in stressful for the body.

The thing that I think is a good takeaway in Peat is that whole fruit is not evil incarnate. I think if you are active and in reasonably good shape it can be a great part of your diet. Still not buying the jugs of OJ though.

do you have any issues with almonds? a friend of mine is allergic to almonds/stone fruit and anything of that sort

I don't know, honestly.
But when come to think about it, eating eggs gives me a slight burning feeling in ny face.
It started since I went primal as I guess everything gets clearer when you cut junk from your diet
I never considered it an allergy, I mean, it's egg, super food and all
Back to experimenting I guess :-)

I don't know if this is the best place to post this, but Mark's recent post of blogs got me to this guy. Seems a good spot given the current discussion. He's got some great stuff for us science minded folks.....I'd start with this one Lucas Tafur: Bioenergetics. He seems to present good data without an agenda (well I'm sure he does have his biases)....but fairly balanced, especially when you consider the crux of this post is mathematically based.

Very interesting stuff. Thanks for posting this, Neckhammer. This guy basically proves mathematically that extracting energy from fat is a much more efficient process when compared to glucose and creates less oxidative stress in the process.

Yeah, I can feel all that stress from my seared ahi dinner. People have lived by coastlines as long as there have been people.

We burn glycogen for a fast burst of energy, to catch dinner or avoid becoming some critter's dinner. Living your whole day in that fight or flight fast burn just strikes me as the ultimate in stressful for the body.

The thing that I think is a good takeaway in Peat is that whole fruit is not evil incarnate. I think if you are active and in reasonably good shape it can be a great part of your diet. Still not buying the jugs of OJ though.

I think even if you're sedentary and overweight you can handle quite a bit of fruit. I think that there are a lot of advantages that fruits have versus vegetables - less anti-nutrients, insoluble fiber and much easier on your digestive system. I will tell you this - eating heavily salted lean beef, lots of fruit, less vegetables and coconut milk for 4 days in a row has had a remarkable effect on my body temperature. I'm much warmer...and I'm deloading from the gym this week. It's interesting.

But yea, no OJ for me anytime soon (unless there's vodka in it). I'll take a couple oranges though if you wanna give them to me.

Don't put your trust in anyone on this forum, including me. You are the key to your own success.

I think even if you're sedentary and overweight you can handle quite a bit of fruit. I think that there are a lot of advantages that fruits have versus vegetables - less anti-nutrients, insoluble fiber and much easier on your digestive system. I will tell you this - eating heavily salted lean beef, lots of fruit, less vegetables and coconut milk for 4 days in a row has had a remarkable effect on my body temperature. I'm much warmer...and I'm deloading from the gym this week. It's interesting.

But yea, no OJ for me anytime soon (unless there's vodka in it). I'll take a couple oranges though if you wanna give them to me.

Perhaps the coconut content is contributing to your temperature rise. Interesting. I've been getting rid of the dairy in my diet and substituting coconut milk and cream and I am feeling really good too. It's hard to say if I'm warmer given that this is summertime in SoCal, but I feel energetic.

I think it also depends on the type of fruit. I eat a lot of berries and right now I have an apricot tree that is producing. (Yum. Nothing like a sun warmed apricot fresh off the tree.) I think some of the tropical fruits give you less nutritional bang for your caloric buck, things like pineapple and mango.

We have had this discussion before but, a 50 year old female body does not work the same as a 20 something athletic male body. So, I think this comes down to a YMMV. If you have everything else dialed in right and still find losing weight to be difficult, maybe try losing (some of) the fruit. Some people do better at a higher carb level and fruit is a perfectly good Primal option for that along with tubers. Some people really have to watch every carb. Yes, special snowflakes.

I think it's a combination of coconut milk, lots of fruit sugar at the expense of starch and large amounts of Himalayan pink salt paired with reduced fiber. I've been taking in next to zero PUFA's, so I'm unsure if that's had an effect. Whatever it is, I like it. I've been getting my carbs from watermelon, apricots and strawberries. Primarily watermelons. I've eaten two whole large watermelons since Monday...

Don't put your trust in anyone on this forum, including me. You are the key to your own success.